The same reason you might use a VPS rather than build your own cloud infrastructure - sure you might save some money, but maintenance is then your problem, scal

The same reason you might use a VPS rather than build your own cloud infrastructure - sure you might save some money, but maintenance is then your problem, scaling down or up is harder and you lose flexibility to move provider. Also there might be some tax incentive if you can put the building down as an ongoing cost to your company.